suggest which state is best for engineering?

You really cannot distinguish on basis of States and secondly when we discuss Government Institutes most of them have good Placements in most of the branches. However on basis of personal experience as well as industrial and employer outlook, I might find a conclusion as follows

Mechanical/Metallurgical/Industrial

Jharkhand/Maharashtra/Karnataka/Tamil Nadu/Odisha/West Bengal

These states have most of the Manufacturing and Operations Industries in India and hence should be preferred when planning a course in Mechanical Engineering with excellent career prospects.

CSE/IT/AI/Electronics

Karnataka/Telangana/Delhi/UP/Maharashtra

IT Hubs at Delhi NCR, Bangalore, Navi Mumbai amd Hyderabad provide excellent career prospects and impetus to training and placements in their respective states. However one should select Metropolitan cities for pursuing education in the above branches for better scope and exposure. Most of the Top MnCs Microsoft, Apple, Google and Intek have their Centres at either of the above Metros.No wonder IIT Hyderabad has been such a steadily rising IIT, having a huge locational advantage. It is only the fourth IIT to be located in a Major Metropolitan City after IIT B,D and M.

Mining /Geology/Geophysics/Environment

Jharkhand/Odisha/West Bengal

Located near Mineral Rich Regions in Chottanagpur Region of Jharkhand and Odisha, the Institutes located in the above states receive excellent prospects from Mining and Geological sectors.

However, I still believe scope of Engineering cant be distinguished on basis of States. Anyone studying in any Institute of the country has excellent chances of succeeding provided he/she cultivates his/hir interest at the correct time and nurtures it through the period of Four/Five Years during Engineering.

All the Best.